linux-kernel - Re: [PATCH] ia64: mca: allocate early mca with GFP

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Tue, 23 Mar 2021 17:47:24 +0000
From:   Sergei Trofimovich <slyfox@...too.org>
To:     John Paul Adrian Glaubitz <glaubitz@...sik.fu-berlin.de>
Cc:     Andrew Morton <akpm@...ux-foundation.org>,
        linux-kernel@...r.kernel.org, linux-ia64@...r.kernel.org
Subject: Re: [PATCH] ia64: mca: allocate early mca with GFP_ATOMIC

On Tue, 23 Mar 2021 16:15:06 +0100
John Paul Adrian Glaubitz <glaubitz@...sik.fu-berlin.de> wrote:

> Hi Andrew!
> 
> On 3/15/21 9:50 AM, Sergei Trofimovich wrote:
> > The sleep warning happens at early boot right at
> > secondary CPU activation bootup:
> > 
> >     smp: Bringing up secondary CPUs ...
> >     BUG: sleeping function called from invalid context at mm/page_alloc.c:4942
> >     in_atomic(): 0, irqs_disabled(): 1, non_block: 0, pid: 0, name: swapper/1
> >     CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.12.0-rc2-00007-g79e228d0b611-dirty #99
> > 
> >     Call Trace:
> >      [<a000000100014d10>] show_stack+0x90/0xc0
> >      [<a000000101111d90>] dump_stack+0x150/0x1c0
> >      [<a0000001000cbec0>] ___might_sleep+0x1c0/0x2a0
> >      [<a0000001000cc040>] __might_sleep+0xa0/0x160
> >      [<a000000100399960>] __alloc_pages_nodemask+0x1a0/0x600
> >      [<a0000001003b71b0>] alloc_page_interleave+0x30/0x1c0
> >      [<a0000001003b9b60>] alloc_pages_current+0x2c0/0x340
> >      [<a00000010038c270>] __get_free_pages+0x30/0xa0
> >      [<a000000100044730>] ia64_mca_cpu_init+0x2d0/0x3a0
> >      [<a000000100023430>] cpu_init+0x8b0/0x1440
> >      [<a000000100054680>] start_secondary+0x60/0x700
> >      [<a00000010111e1d0>] start_ap+0x750/0x780
> >     Fixed BSP b0 value from CPU 1
> > 
> > As I understand interrupts are not enabled yet and system has a lot
> > of memory. There is little chance to sleep and switch to GFP_ATOMIC
> > should be a no-op.
> > 
> > CC: Andrew Morton <akpm@...ux-foundation.org>
> > CC: linux-ia64@...r.kernel.org
> > Signed-off-by: Sergei Trofimovich <slyfox@...too.org>
> > ---
> >  arch/ia64/kernel/mca.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/arch/ia64/kernel/mca.c b/arch/ia64/kernel/mca.c
> > index d4cae2fc69ca..adf6521525f4 100644
> > --- a/arch/ia64/kernel/mca.c
> > +++ b/arch/ia64/kernel/mca.c
> > @@ -1824,7 +1824,7 @@ ia64_mca_cpu_init(void *cpu_data)
> >  			data = mca_bootmem();
> >  			first_time = 0;
> >  		} else
> > -			data = (void *)__get_free_pages(GFP_KERNEL,
> > +			data = (void *)__get_free_pages(GFP_ATOMIC,
> >  							get_order(sz));
> >  		if (!data)
> >  			panic("Could not allocate MCA memory for cpu %d\n",
> >   
> 
> Has this one been picked up for your tree already?

Should be there: https://www.ozlabs.org/~akpm/mmotm/series

> #NEXT_PATCHES_START mainline-later (next week, approximately)
> ia64-mca-allocate-early-mca-with-gfp_atomic.patch


-- 

  Sergei